Phenyl ureas, their use as selective herbicides

ABSTRACT

WHEREIN R1 is an alkoxyalkyl or alkylthio alkyl radical and R2 is hydrogen, a lower alkyl or lower alkenyl radical, HERBICIDAL COMPOSITIONS CONTAINING THEM AND THEIR USE AS SELECTIVE HERBICIDES ARE DESCRIBED.   Compounds of the formula

1 United States Patent 1191 1111 3,864,395

Martin et al. Feb. 4, 1975 [54] PHENYL UREAS, THEIR USE AS 1,501,293 11/1966 France 260/553 A SELECTIVE HERBICIDES [75] Inventors: Henry Martin, Basel; Otto Rohr, P imary E in r-L on Zitver Th l B mmg n; Assistant Examiner-Michael W. Glynn Stefan Jfl B8561, of Attorney, Agent, or FirmHarry Falber; Frederick H. Switzerland; Georg Pissiotas, R bi Loerrach, Germany; Werner Toepil, Basel, Switzerland 73 Assignee: Ciba-Geigy AG, Basel, Switzerland 57 ABSTRACT [22] Filed: 1971 Compounds of the formula [21] Appl. No.: 187,831

Related US. Application Data R [63] Continuation-impart of Ser. No. 816,375, April 15, I t 1969, abandoned. 1 0 NH CO \I CH [52] US. Cl...... 260/553 A, 260/552 R, 260/453 A, Cl 3 71/120 CL 127/18 wherein R is an alkoxyalkyl or alkylthio alkyl radical [58] Field of Search 260/553 A d R is hydrogen, a lower alkyl or lower alkenyl [56] References Cited dical,

S0|0Way et al.............. A X l tl I '1 l I l FOREIGN PATENTS OR APPLICATIONS 2,006,525 12/1969 France 2 Claims, No Drawings PHENYL UREAS, THEIR USE AS SELECTIVE HERBICIDES CROSS REFERENCE This is a continuation-in-part of our application Ser. No. 816,375 filed Apr. 15, 1969, now abandoned.

The present application relates to compounds of formula /R2 R NH CO N wherein R is a lower alkoxy-lower-alkyl or a lower alkylthio-lower alkyl group with up to l-4 carbon atoms per alkyl moiety,

R is hydrogen, a lower alkyl or lower alkenyl with up to 4 carbon atoms in the radical.

The term lower alkyl or alkoxy or alkylthio groups, as applied to the substituent R, means those groups which possess l to 4, preferably 1 or 2, carbon atoms and which may have straight or branched chains, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec. butyl or tert. butyl.

The lower alkyl groups which are possible for R may possess l to 4 carbon atoms, but preferably contain only I or 2 carbon atoms. The lower alkenyl groups which R, can represent possess 2 to 4 carbon atoms. Alkenyl groups especially preferred are those possessing 3 or 4 carbon atoms; the methallyl or Z-methylpropenyl (l) residue may be mentioned as examples.

The manufacture of these compounds is carried out according to methods which are in themselves known, for example by reaction of a compound of formula with a compound of formula 3 (III) wherein R, and R have the significance indicated above, and A and B denote residues which can form areas by addition or condensation. In the present process, one of the two groups A and B represents an amine, whilst the other represents a urethane, a carbamoyl halide, a urea group or especially an isocyanate or isothiocyanate group. In the latter case, it is necessary to carry out a post-treatment with an oxidising agent, for example, HgO, Cl /H O or COCl /H O, in order to replace the S atom by oxygen. lf R represents hydrogen another substituent R may be introduced by appropriate posttreatment, for example by alkylation or alkenylation. lf R is intended to represent the 2- methylpropenyH l group, then as suitable starting materials, there may bementioned especially the corresponding phenylisocyanate on the one hand and. as the amine, isobutylidene-N-methylamine on the other.

The working conditions used are those usually employed for the formation of urea from isocyanate and amine, with the desired. N-methyLN-Z-methylpropenyl( l )-urea being produced in one process stage through displacement of the double bond.

The compounds of formula (I) possess pronounced selective herbicidal properties and are especially advantageous for combating weeds in culture plants, especially in cultures of grain, maize. cotton and legumes. The term "grain is used herein to mean especially wheat, barley and rye, the term "legumes" means especially soya. The action is not restricted to broad-leaved weeds. but also manifests itself to the same degree in the case of grass-like weeds. The use of a sufficiently large amount results in total herbicidal effect. The active substances can be used both in the pre-emergence and also in the post-emergence process. The amounts used can vary within wide limits, for example, within the range of from 0.1 to 10 kg of active substance per hectare, but preferably 0.5 to 5 kg of active substance per hectare are employed.

Compounds of formula I with especially advantageous selective properties have the methoxy-methylmethoxy ethyl, methylthio-methoxy or ethylthio radicals as R and hydrogen or the methyl group as substituent R The present invention also provides a herbicidal preparation, which comprises, as active ingredient, a compound of the general formula (l) together with a suitable carrier. Other additives may also be present. Suitable carriers and additives may be solid or liquid, and are substances which are usually used in formulation technology for example natural or regenerated mineral substances, solvents, diluents, dispersing agents, emulsifiers, wetting agents, adhesives, thickeners, binders or fertilisers. Furthermore, other herbicides may also be added. Such herbicides can, for example, belong to the class of the ureas, the saturated or unsaturated halogen-fatty acids, halogenobenzonitriles, halogenobenzoic acids, phenoxyalkylcarboxylic acids, carbamates, triazines, nitroalkylphenols, quaternary ammonium salts, sulphamic acid, arsenates, arsenites. borates or chlorates.

When used in pesticides, the compounds of formula (I) may be processed as dusting agents, emulsion concentrates, granules, dispersions or as sprays, for example for gas phase application in greenhouses, as solutions or suspensions of the usual formulation, which is part of the general knowledge of application technology. Compare the relevant data in US Pat. No. 3,329,702 or British Patent l,047,644 or Swiss Patent 424,359.

The following Examples illustrate the invention.

EXAMPLE 1 tion of the addition, the solution is further stirred for about 4 hours, after which the N-{3-chloro-4-(B- methoxy)-ethoxyphenyl)-N,N-dimethyl-urea of formula (compound 1) which has crystallised out is filtered off. Yield: 26.2 96 7:. After recrystallisation from a benzene/petrol mixture, the melting point is about 94- 95C.

l kg of active The following compounds were manufactured analo- Plum 2 kg of gously: substance per substance per hectare hectare '5 l l Zea 2 3 2 Digitaria 9 9 7 R1 NH co N Panicum 6 Poa 7 6 CH 'Alopecurus 6 Galium 8 7 7 Calendula 9 9 9 Cl Chrysanthemum 9 9 9 Brassica 9 9 9 lpomoea 9 9 9 Compound R, R Melting point Stellaria 8 8 8 No. in "C Amaranthus 9 9 9 2 cH,,ocH,- CH, 129 |30 Code: 3 C H,-,0C H CH3 l-IO Ill l no damage 4 CH3SCH4 CH3 I00 l0] 3 damage which can still just be tolerated 5 C a CHz- H I43 I44 9 total damage 6 CH;,OC H, H I26 l27 7 C H OC H H 14! I42 8 C H,-,OCH H I35 I36 9 CH;,SCH H 136 137 EXAMPLE 3 g fi' ii The compounds Nos. 2 and 5 were compared in pre 12 B Z L CH 53 60 and post-emergence application with the compounds 13 Z b 2 i 1, b0i|in8 Pflint A N-(3-chloro-4ethoxyphenyl)-N'-methyl-N'- l92C/0.00lmm mbut I urea 14 n-c,H,oc H.- CH, 40 42 Y l5 CH,,SCH,- CH, 74 76 B N-(3-chloro-4-ethoxyphenyl)-N ,N -dtmethyl l6 C,H,-,SC,H,- CH 74 76 urea,

EXAMPLES OF FORM ULATlONS Dusting agents Equal parts of an active substance according to the invention and precipitated silica are finely ground together. Dusting agents, which preferably contain 1 6 7c of active substance, can be manufactured therefrom by mixing with kaolin or talc.

Spraying powders In order to manufacture a spraying powder, the following compounds are, for example, mixed and finely ground:

50 parts of active substance according to the present invention 20 parts of Hisil (highly adsorbent silica) 20 parts of bolus alba (kaolin) 3.5 partsofa reaction product of p-tert. octylphenol and ethylene oxide, and 1.5 parts of sodium l-benzyl-2-stearylbenzimidazole-6,3-disulphonate. Emulsion concentrate Easily soluble active substances can also be formulated as an emulsion concentrate in accordance with the following instruction:

20 parts of active substance 70 parts of xylene, and 7 10 parts of a mixture of a reaction product of an alkylphenol with ethylene oxide and calcium dodecylbenzenesulphonate both known from the French Patent No. l,50l,293.

As testing liquor a 1% sprayable dispersion obtained from the following composition by dilution with water was used.

50 of one of the compounds No. 2, 5, A or B,

33.5 of Bolus alba (kaolin),

l l of the ammonium salt of ligninsulfonic acid,

4.5 of sodium dinaphthylmethanedissulfonate (a product commercially available'under the tradename Neradol"),

l 72 of a mixture of 40 parts of alkylarylpolyethyl alcohol and 60 parts of magnesium carbonate (a product commercially available under the tradename Triton X Pre-Emergence Application:

The plant seeds were sown in a series of earthenware pots in a greenhouse. One day after sowing the pots were sprayed with the testing liquor. The amount of spraying liquor corresponded to 1 respectively 2 kg of active substance per hectare. Evaluation took place 20 days after sowing.

Post-Emergence Application:

The plants were sown into trays filled with earth in a greenhouse. When they had reached the 2 to 3 leaf stage, about 12 days after seeding they were sprayed with the testing liquor so that the final amount of active substance applied corresponded to 1 respectively 2 kg per hectare. The assesment ofthe test was made out l8 days after the treatment and the plants were evaluated according to the following key:

I 2 plant not or only slightly damaged pre 3 5 medium but recoverable damage to plants 6 8 heavy damage 9 plant killed The results are summarized in the table below.

T a b l e No. 2 No. 5

pre post pre post Compound tested in preand postemergence appli cation, concentration in kg/ha Triticum Hordeum Avena Zea Oryza Digitaria Sorghum Panicum Poa Alopecurus Beta Galium Calendula Chrysanthemum Linum Brassica lpomoea Stellaria Soja Gossypium Amaranthus In these tests compounds N0. 2 and 5 show excellent dimethyl urea. selective herbicidal activity in preand post-emergence 2. N-(3-chloro-4-ethoxyethoxyphenylJ-N ',N- application towards wheat, and in post-emergence apdimethyl urea.

UNITED STATES PATENT. OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,864,395

DATED February 4, 1975 INVENTOR(S) -.Henry Martin, Otto Rohr, Dieter Duerr, Stefan Janiak,

Georg Pissiotas, Werner Toepfl It IS certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

The following should be inserted in the heading:

Foreign Application Priority Data April 19, 1968 Switzerland. .5829/68 Signed and Sealed this twentieth D y of January 1976 I [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofPalenrs and Trademarks 

1. N-(3-CHLORO-4-METHOXYMETHOXYPHENYL)-N'',N''-DIMETHYL UREA.
 2. N-(3-chloro-4-ethoxyethoxyphenyl)-N'',N''-dimethyl urea. 